Would the letters RE within a circle, or the letter X within a circle indicate a factory reblue has been done? The letters are stamped into the frame under the stocks on an N frame revolver made about 1972.

No. Over the years a re-blue has been designated by R-S(re-finish standard [blue]), R-B(re-finish blue) the same in a box or even in a diamond. Those are inspectors/fitters marks. If it were a re-Nickel it would be shown as R-N with the same variations. This applies regardless of the original finish, regardless if it were a change of finish or re-finish as original.

Not to say the gun hasn't been re-blued, just not by the factory if it has.

Thanks for the response. If this is a reblue it is sure a good one. It is hard to tell.

I have the same mark on my 29-2 shipped Nov 1972. I was told by a factory service rep that this was the fitter's mark.

Dave